In some types of integrated circuits, such as integrated circuits used in communication applications, there may be a need to discriminate between different frequencies of an input clock signal supplied to the integrated circuit. In this respect, it is known to use programming, e-fuses, clock specific programs or specific signals which are supplied from the outside to the integrated circuit to indicate which frequency of the input clock signal is used. For example, a signal supplied to a dedicated input pin of the integrated circuit may be used to indicate which one of a high frequency and a low frequency is used. The integrated circuit may use this information to adjust its internal operations. However, this known approach has the problem of a low flexibility or of requiring additional processing so as to adopt the integrated circuit to the specific frequency of the input clock signal.